In Mahayana Buddhism, a Bodhisattva (Sanskrit: a person bent on and striving for Enlightenment) is a being with the determination to aid others, out of compassion, on their quest for the highest state of liberation, Nirvana. Having remained in this world of endless rebirth (Wheel of Life), this individual has taken the Bodhisattva's vow not to attain Enlightenment until all other beings have achieved liberation.

In Theravada Buddhism, the Bodhisatta (Pali) is an aspirant striving for Enlightenment, so that once Awakened, he or she may efficiently aid other beings with the expertise of supreme Enlightenment. In the holy Tipitaka, Siddhattha Gotama's life experience as a bodhisatta before Buddhahood is recorded in the texts of the Jataka. Lay Buddhists of Theravada seek inspiration in Gautama's skill as a good layman in these text (which account not only tell of his historical life, but many previous lives). A famous, and presently practicing bodhisatta, is Maitreya (Pali: Metteyya), the soon future Buddha to be who is currently residing in the Tusita world awaiting future rebirth.

A bodhisattva practices several virtues, called the paramitas. Once attaining full Enlightenment, the bodhisatta becomes an Arahant, has 'done what had to be done' and is never again reborn into the Wheel of Life. A later development in the Mahayana school, drawing influence from the Hindu religion, is the ability for bodhisattvas to control their future rebirth, and in doing so, almost angelically saving the unfortunate and secular. This new ability takes on not rebirth but reincarnation, alien to Buddhism law, and is denied by the Theravada school of thought which is known for its orthodoxy.

Various traditions within Buddhism believe in certain specific Bodhisattvas. Some Bodhisattvas appear across traditions, but due to language barrirers, mistakenly are seen as separate entities because of the different names and titles. For example, Tibetan Buddhists believe in Chenrezig, who is Avalokitesvara in India, Guan Yin in China, and Kannon in Japan. A modern bodhisattva for many is the 14th Dalai Lama, considered by many as the incarnation of the Bodhisattva of Compassion.